Magnetic tracking device.



FI G. LYNDE.

MAGNETIC TRACKING DEVICE.

APPLlcArloN msn JAN.28,1915.`

1,167,087. I Patented Jan. 4, 1916.

INI/ENTOR .WIT/VESSES pjmzz i r UNITED sTATEs PATENT oEEIcE.

FRANK G. LYNDE, OF NEWARK, NEW JERSEY, SSIGNOR v'JTO LAUTER COMPANY, OF

' NEWARK, NEW JERSEY, A CORPORATION OF NEW JERSEY.

MAGNETIC TRACKING DEVICE.

Specification of Letters Patent.

Patented Jan. 4f, 1916.

Application filed January 28, 1915. Serial No. 4,827.

T 0 all whom it may concern Be it known that I, FRANK G. LYNDE, a citizen of the United States, residing Yin Newark, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Magnetic Tracking Devices, of which the following is a specification. Y c

My invention relates to improvements in tracking devices for maintaining cooperative registry of the perforations in lnusic sheets with the vents in the tracker-bar of player pianos.

One ofthe objects of my invention is to provide a simple form of valve closing means in pneumatically actuated tracking devices, Which means will cause the least possible wear on the traveling sheet, which will be instantly responsive to any lateral wandering of the sheet and which will be free of any necessity to repair, adjust or replenish any of the parts thereof.

Various other objects and advantages of the invention will be in part obvious from an inspection of the accompanying drawings. and in part will be more fully set forth in the following particular description of one form of mechanism embodying my invention, and the invention also'consists in certain new and novel features of construction and combination of parts hereinafter set forth and claimed.

Referring to the accompanying drawings: Figure 1 is a horizontal sectional view through a tracker-bar provided with a preferred embodiment of my invention; and Fig. 2 is 'a front elevation of the device shown in Fig. 1.

There is illustrated a portion of a player` piano spool box 3 including a tracker bar 4 provided with ducts 5 across the face ofs.

which bar is drawn the perforated music roll 6 unrolled froln the upper spool 7. This spool is shifted laterally in either direction through the agency of some suitable pneumatically actuated mechanism indicated diagrammatically by the pneumatic 8, due to change of pneumatic pressure in either of the air ports 9 at opposite ends of the tracker bar. These ports are each closed by valves 10 having stems 11 slidably mounted in the tracker bar for movement toward and from each other and transversely of the travel of the sheet. Each valve stem has an outturned finger 12 projecting through small slots 13 in the face of the tracker bar and the fingers I are so spaced apartthat the sheet fits, therebetween when the fingers are in their limited position closest together. A permanently inagnetized bar magnet 14 is mounted on the rear face of the tracker bar in line with the valve stems and positioned between the same.

The valve stems, the fingers, or at least the portions thereof adjacent the ends of the magnet are kof iro-n so as to be attracted by opposite poles of the magnet and the valves and their stems are preferably of such a length that each valve' is firmly seated over varying. the magnetic strength of the magnet 'but while the magnet should be designed lso as to Insure an air-tight fit of the valves' against the ports, the pull of the magnet should not be so strong as to injure the edge of the music sheet assit presses against the projecting fingers. Should the sheet wander from its normal position one or the other of its edges will bear on the finger "in its lateral path of movement and acting against the magnetic pull of the bar 14 force the valve on the shifted side away from its port. This opening of the port to-the atmosphere will inaugurate the actuation of the sheet shifting device to replace the sheet in its normal position as is usual with devices of this character.

The release. of the pressure of the sheet against the shifted finger will permit the magnet to act thereon and return the valve` to its normal port closing position.

By means of a device of this character a positive closing of the air ports is insured and a steady uniform engagement with the shifted sheet is attained which engagement is independent of temperature changes, can be 'maintained without the necessity of replenishiug electric batteries or supplying any source of power.

As the force acting on the valve is at its maximum only when the sheet is shifted slightly, any running wild of the music sheet be understood that -various omissions, substitutions and changesin theforin and details of the'device illustratedand inits op-' eration may. be made b thosefskilied in the art without departing rom the :spiritof the invention.

Having thus described claim: A A r Y 1. In a device of theclassdescribed, the combination of va valve controlling finger adapted to be actuated by the lateralv wanderings from normal ofthe edge of a trav- Y`my invention, I

.eling sheet and a magnet'having one of its poles positioned l'adjacent to andl acting on said finger to draw the'sametoward the nor'- mal position of thesheet andtending to maintainthe valve in set position.

2; Inl av player piano .provided with a tracker bar, the combination of a pair of fingers 'projecting through v-the b ar vand adapted Vtohave theiiiusicsheet fitted therebetween, valves for Vcontrolling sheet' shifting mechanism operatively'controlled-by the shiftingv ofthe sheet-'agalinst saidfingers, a barv magnet vfixed to .the tracker .bar and positionedbetween and acting on said fingers to vdraw the same towardl the adj acent edges of the music sheet. v. a l 1 3. In a. playerpiano, shee't shifting mechanism operatively controlled by the lateral wanderings of the music sheet, a permanent magnet operatively associated with said mechanism to maintain parts thereof resiliently in engagement Vwith the edges of the music sheet when traveling out of its normal athf". Y p 4. I`na "player piano; a sheet shifting mechanism including a sheet engaging member, means acting on said member tending to move the same in adirection toward Vthe normal path 'of the music sheet, said means acting'on said member with a pressure decreasing in intensity as the member is moved 'in a' direction away'from the normal path of the-sheet whereby fi'n case' the sheet runs wild it will be engaged by a pressure .rela- -tively `light compared with` the pressure thereon while the fsheet is wandering but a' slight distance from its normal path..

5; In a player piano, the combination. of a pneumatically actuated sheet shifting mechanism, and a magnetically actuated control for governing the actuation of said mechanism.

6. 4In a player piano, the combination of a pneumatically actuated sheet shifting mechanism including a valve and a magnetically actuated control for governing the actuation of said valve. f

.7. In a self-pla ing piano, sheet shifting mechanism inclu ing a valve opening, a valve foi controlling said'opening, means Voperatively connected to said valve and controlled by the wanderings of the music sheet for'actuatin said' valve and for moving the lsaine from its normal position and energie means being immovable and fixed in posi- 'tion and acting 'on'` said valve tending to Vmaintain the same 1n normal position, said energie means, constituting a stop for limiting the movement of said first named means.

8. In a self-playing 'piar'io, the combination of a pair of armatures spaced apart a distance to accommodatea music sheet therebetween, a single bar magnet disposed be-l tween and having its' opposite poles operatively acting upon said armaturesto draw Y the same toward the path of the music sheet and mechanism operatively controlled by said armatures.` l'

9. In a device of the class described, the combination with a sheetv edge engaging member, means acting'on said. member to force the same toward vthe normal path of travel of the sheet, said means exerting a variable tension on said member inversely proportionate to the distance of the member from said normal path whereby when the sheet is running wild the edges thereof will be engaged by a pressure materially less than the pressure when the sheet is wandering but slightly from its normal path.

10. In a player piano, Aa sheet controlled mechanismincluding an armature adapted to be operatively actuated by the sheet and a magnet for said armaturedesigiied to maintain said armature in normal position.

11. A valve structure including a valve opening, a valve for said opening and a.

permanent magnet operatively .acting .on said valve to maintain the samein position closing said opening. i

Signed at Newark, in the, county of Essex and State of New Jersey', Athis 26th day of January, 1915.

, 'FRANK G. LYNDE. Witnesses:

H. R. BAUER, S. R. CAIRNS. 

